Applying/earning/validating leave
Solution 1:
The user is receiving a "leave credit" for attending the event. When they need to take time off, they're requesting leave. I'd use:
- Apply for Leave Credit
- Request Leave
I think most English speakers will understand this.
Solution 2:
For the first action I would use something like:
- Apply for additional leave
- Amend leave entitlement
- Submit change request
- Update available leave
And for the second, something like:
- Submit leave application
- Request leave
- Book leave
Solution 3:
Apparently you are asking for suggestions for names of two actions or forms, on the one hand a granting or obtaining of credits toward future leave, and on the other application for specific leave dates.
Phrases for case 1:
- Add to accrued leave
- Record credit for future leave
- Update accrued leave credits
- Update leave credits
- Submit leave credits
Phrases for case 2:
- Approve leave dates
- Approve leave schedule
- Apply to take a leave
- Apply for leave
- Set leave dates