It's more like "The contract doesn't say we CAN'T do this, so we can" as far as scheduling is concerned. Even if it DOES say they can't, they'll try it and see if you catch it. Most of the reserves aren't even getting 10 days off. With the extensions (we get one refusal a month per the contract) and junior mans (no contractual refusals), you normally get reduced to 8 or 9 days off a month. You can refuse more than one extension or a junior man, but you got some splainin' to do with base management.
With the exception of today (sat for 8.5 hours and they didn't use me. I bugged them so many times they released me a 1/2 hour early), I normally sit RR for 6-7 hours then get called for a trip that ends 4 hours later. If you get a duty period of less than 11 hours, consider yourself lucky. Reserve will be on a reduced rest overnight while the rest of a crew is on a high speed. Why? They can add more flying to you when you get back to base if it's a reduced rest overnight. Now, if it's less than 9 hours rest, they can only use you for 12 hours. Pretty much every time I've had that happen, they use me for 11:55 or so. I had one where I was at 11:59 duty. Somewhere there was a scheduler dancing because it fit my schedule so perfectly.
You'll get DHed out of domicile to do flying, teased with a DH home, show up to the gate only to find out your reservation has been canceled and crew scheduling wants you to call them. Then you get the word you've got another out and back, and you'll DH home on the next flight. Rinse, repeat for two days. That was my weekend in DTW last weekend. I just pack for 5 days every time now just in case.
You'll fly a highspeed, followed by 10 hours of rest, a 2 day with a 18:55 show for a reduced rest overnight (legal since you just came off 10 hours rest), a 5 leg day, then another high speed. Reserves here call in fatigued way more than line holders, and management scratches their heads wondering why we're tired all the time.
The last TA that came out added one more option to the list posted above as to what they can do when you complete an assignement: back on reserve for 12 hours. That would have been the new default, but the TA (thankfully) got shot down. Word is, the new one is they can hold you at the airport for 3 hours instead of 1, but I also heard from a rep today that the min day may or may not make it through in negotiations. Now, if I fly one leg, and they hold me for 3 hours, I might be okay if I know I'm gonna credit 4 hours or the greater of flying assigned. If that goes away, and I sit at the airport for the same pay as the one leg I just flew, no thanks.