Swap pets at 25 and communicate pet levels to auto level pets using a 'slave toon' who's auto forfeiting.

Tropic try this and let me know what you think.
See forums for setup but quickly:

P1 (main) lock slots 2 and 3 and select 'swap pet at 25 in options'. select WT and join pvp
(assume pets are 1-1-25)
P2 (slave) lock slots 1 and 2 , select WT/Auto Forfeit and set forfeit timer to 1
(assume pets are 25-1-1 and you have enough pets to cover the level jumps)

Click Join pvp on P2
Click Join pvp on P1

Battle should start, P1 will gain 5-6 lvls on the  win
P1 will send team info to P2
P2 should swap slot 3 (only free slot) to a pet around the same level (+1,0,-1 of P1's pet)
Battle should re-queue.

NOTES:

I've found if you don't open the pet journal before you start the setTeam can cause an error due to that update at the end of it

Queue check timer is now 5 seconds (not 1) to solve some sync/timing issues - specifically swapping pets and stop/starting pet battle seems to cause blizzard issues if it happens fast

If a queue timers goes for more than 5 minutes (I've seen it be like an hour - I think it's blizz confused about being in/out of queue) We stopPVP. Then the 5 second timer kicks in and we startPVP. This seems to cure the bad queue. We can likely adjust this to less than 5. This timing issue seems to be exacerbated by the swapping of pets but I can't see an error that causes it specifically. I think their pet battle stuff just gets out of sync because we're quitting,changing pets and queuing too fast.

Ian