Timer Issue with DD-WRT v23SP2

I hope this isn't too off-topic for the group...

I have a Buffalo WHR-G54S running DD-WRT v23 SP2 firmware. For the
most part, this setup is great. (The DD-WRT firmware has been quite
the "breath of fresh air" after a number of disappointing experiences
with other devices on the market and their firmware.)

One of the things I want to do is shut off access to the Internet for
a certain number of hours. This was easy enough to do, but the time
span crosses over midnight. DD-WRT won't allow this, and says that the
end time must be later than the start time...the block starts at 10 PM
(22:00) and goes until 9 AM the next morning.

For now I've solved the problem by creating two rules. The first
covers 22:00 to 23:59. The second then takes over immediately at 0:00
(midnight) and runs until 9:00. This is fine, although it takes up
more of the limited (ten items) rule listing than I'd like it to.

Is there any way around this?

William