We know that there isn't a RTC and there will not be in the future.
The problem is that when we make a screenshot, the file will be numbered with the first number free among the pictures already on the memory. (A)
Instead of that, I think it would be better if the new file would be numbered with a number after the higher already present, also if there are numbers free because pictures have been previously deleted. (B)
Another option is a sequential number: the scope keeps logged the last number used and for the next picture he will give the next number. (C)
A): files on the memory: 1, 2, 3, 5, 6, 7, 8. The next file, the last, will be number 4...
B): files on the memory: 1, 2, 3, 5, 6, 7, 8. The next file, the last, will be number 9.
C): memory #1: files 4, 7, 8, 11
memory #2: files 1, 2, 3, 5, 6, 9
The last file saved by the scope is number 11. The next file will be 12, wherever I will write it. It will be also possible to reset the counter or renaming the last file saved: after saving a file I can go to the rename function or do nothing.