At present if a hold is placed and no explicit expiry date is set the expiry is set to null. Libraries want a default expiry period to be used. Add a system parameter for default expiry and instead of defaulting to null set to today + period period = 0 will give the present behaviour
Bug versionned for master. entries will be made against rel_3_8 once the patch has been applied (see thread about that on koha-devel yesterday)
This has been resolved on another bug report. We now have DefaultHoldExpirationdate to make sure holds expire.