If it's a big amount it's ok not to be ok you should get your withdrawal based on the time they set that you should receive it, if we have not known that there was an issue like this in the past like the hot wallet not getting refilled we will think that Bitvest is turning to scam but still give them a chance at least for another 2 days but keep getting in touch on their support, btw can you tell us the amount and of course you can prefer not to tell us, but in case you've waited long enough you can create a thread in the scam section to get their attention, be sure to follow the right format and include all your pieces of evidence.
I think bitvest don't give an exact time for their withdrawals because they know that it can be delayed and doing so will only make their costumer more angry towards them.
If some don't know this issue or shall I say don't like to read feedback before they play then they can easily end up on a sticky situation like this but for those are a previous player of this site and bitvest have done great things to their life then maybe they won't bother about this known issue but will continue playing there. The guy can pm the amount in private if he is too shy about it but it doesn't matter. Small or big amount, it was still a money and must be paid.
Well over a week now, no other casino online takes over a week to process a withdrawal.