Mastermind pets die when I level up during a mission

I was just playing my thugs/poison mastermind.

I was inside a warehouse mission, fighting family.
Most of my pets were at full health or very close to full hp.
On defeating another enemy, I dinged and levelled up to 28.
We were still in mid-battle and fighting a boss.

As I levelled, ALL of my pets flopped over dead. BAM.
I was left petless, wondering WTF just happened.

My team mate (we were in a duo) who is also playing mastermind, said that this has been happening to him also. That all of his pets die whenever he levels.

Note that we did not change leadership nor missions or anything for that matter. We were mid battle, with pets, busy attacking, I dinged and then I had no pets left.

I don't recall this happening the last time I played a mastermind (about 6 months ago). Is this a new bug?? If so, this would be bloody awful if you levelled killing a minion whilst also fighting an AV. *shudders*

And yes, I did file a ticket to support in game.
I was just wondering if anyone else had experienced this awful problem.

Edit - note added for further clarity/info.
*note* My team mate levelled, and his pets did not die. We have come to the conclusion, that, if you are NOT the mission owner, and you level, your mastermind pets will die. And if you ARE the mission OWNER, you can level and your pets will stay alive.

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Further to this specific bug, I have experienced some other awful problems with mastermind pets, including:

• I was a level higher than my team mate (he is on a mastermind). I picked his mission, and all of his pets died as a result.

• Same thing happens when changing leadership to someone who is lower in level to the prior team leader - doing so will kill the mm pets.

• Mastermind pets don't like some elevators. We have discovered that going up the elevators on the first floor in most maps, will send our pets berserk, either leaving them behind on the ground floor, or having them run off in an annoying loop. Even my veteran buff pet didn't want to follow me up the elevator.

• Exiting maps will screw up my pets as I zone. Usually half or more of my pets will no longer be under my control and will have a blue border on them, and I can no longer give them commands.

• Exiting maps or zoning results in my pets losing all buffs, including the upgrade henchman buff. I keep forgetting they have lost their buff and disadvantaging myself in battle as a result.

Ok now this is getting annoying.

The problem seems to be intermittent.

I just zoned again, and this time all my pets remained under my control and all kept the upgrade buff.

But my team mate lost control of ALL of his pets.

Seems this bug is very random.

From my exp it depends on if the game spawns the pets before you make the final step in.

Anytime the pets beat you into the world they are semi independent agents (unless someone on your team tries to buff them...this makes them yours again).

Yep, there are quite a few annoying bugs with the MM pets at the moment. (Suddenly finding myself being pounded on by a longbow ambush after entering the bank in a mayhem and my pets are god-knows-where is my favourite )

FWIW, the pets seem to go AWOL less often if I put them in passive follow before an elevator. I have no figures to justify anything and it could be pure luck, but it might be worth a try.

Anyway, as far as the pets dying thing goes, in my experience, it happens when I'm exemplared (i.e. on a team where I'm not the leader -- I've *never* had it happen solo). I wonder if what's happening is that I level, pets go up a level, then the exemplar-leash yanks me back to the same level as the team leader, and the pets die because of the drop, like they always do if you drop a level from when you summon them.

I get similar issues with my pets though if I exit a mission and they are there but uncontrollable (show up as unowned), I try to find an entry point (AE, zone, whatever and wait a few seconds,they usually rejoin me.
It is weird to see them run out en mass as I run into the university but that isn't really an issue.
What really got me was tonight as I was playing my Traps/Mercs doing my mayhem mission. I entered the arson side mission and lo and behold... just me and my force field emitter. Then the Longbow started coming. Thankfully I was able to run back out and a few of my guys (both my spec ops) rejoined, but no one else. More Longbow showed up...
I ran around, threw down all the traps I could and ran BACK in the arson building. A few more mercs rejoined and I ran back out again. Fun, fun...
Finally, I had all my guys and proceeded to defeat the Longbows harassing me.

I figure this uncontrollability happens if you enter a mission or area too close to an ambush spawn. Thankfully, my guys are almost always set on offensive so even if they don't respond to commands, they try to take the baddies down.

The only other issue I have with Masterminds, is that usually without fail, my medic or arsonist (depending on the powerset) likes to go up close and personal.
With the arsonist, I basically didn't count on him for most of 5 or so levels because of this. The medic, however is paramount as I only have triage beacon for healing outside of slapping inspirations on the guys.

I know you can bind macros (like on specifically for the medic to keep him on me, for example) but I am not confident with the idea of messing around with that yet.