If the shop doing the evac / refill is not willing to evac over night you will want to replace the receiver/dryer as well. Humidity plus freon = acid that will corrode your system from the inside out. The receiver dryer has a desiccant to absorb any moisture that gets in the system from opening it up.
You might get away without it if you are able to change the condenser rapidly.
A good shop should be set up to recover the freon in the system before you take it apart. The recovery machine should be setup to recover and measure your freon and any oil that comes out with the freon. When you refill the system you put the same amount back in. you will get pretty much all the freon out, but not all the oil.
You might ask if they will recover your freon and oil at the end of the day. Then you go home and swap out the condenser and maybe receiver/dryer. Head back to the shop first thing in the morning for them to evacuate the system and refill with your freon and oil. That way you should not have to pay for any freon or oil.