Dear @sun-73,
All strategies that are sent before contest deadline will be processed and eligible for participating in the contest, even if they finish with processing later.
The limit of 15 strategies per contest remains the same, but that doesn't mean one user can't submit more than 50 strategies. He just has to pick which 15 of them to send to contest, and if he doesn't, then the 15 best sorted by Sharpe ratio will be considered as participating in the contest.
The strategies of other users, or their number, will not make your strategies exceed limits and filter them out. If you suspect that some strategy shouldn't be filtered out by time limit constraints, you are free to submit the same strategy again. Maybe it will work the next time, and if not, then there is probably some issue with the strategy itself.
Regards