The option to set an expiry date to custom offers should really be implemented for offers you send to BRs too.
As it is, it’s hardly possible to send offers to especially requests with a higher budget that require hours, days, even weeks to complete.
The fact that a buyer you sent such an offer to, could suddenly accept it completely out of the blue after you have long forgotten about it, together with the fact that you can get bigger direct orders without buyers contacting you prior to ordering, combined with the issue that we can’t set a max for gig multiples buyers can order in Writing & Translation, makes planning your schedule and managing your workload a game of luck.
I would send/would have sent more offers to BRs if that option existed there too, just like in the “normal” custom offers you can send.
In case the reason for no expiry date option is the thought that buyers would complain that some offer they were considering did expire while they still were waiting for more offers to come in, there could either be a minimum of 3 days perhaps.
The ideal solution from my POV though would be to let sellers choose any expiry date and adapt the code so that expired offers show a note that the seller did set an expiry date for the offer for reasons of planning security but can be contacted (link to seller profile/Contact Me button) to ask if the offer would still be valid with the same/a different deadline.
Then, the seller could send the offer again, with the same (if possible) or a different delivery time.
Alternatively, and in any case, it would be great if we could somehow see when a BR we sent an offer to has been given to someone already.