3 season and liner. Take for the extreme and kit down accordingly. If it gets very cold, boil water before you go to bed and put it in a bottle at the bottom of your bag, (amazing how warm your whole body gets) and then in the morning you got the water to drink or wash yourself with etc….
go prepared
this time of year it will be quite warm so if it is very hot sleep in your liner and just have the sleeping bag there as a back up 😀
thought of everything 8)