Yeah i had that a lot, i found that i could actually sleep whenever i wanted when i got sober, iwas very lucky that i didn't work for the first 6 months and could have as many afternoon naps as i wanted...quite a standing joke at AA actually as i would turn my mobile off when having a snooze, he must be having another kip:-)
What a total gift it is to be able to sleep like that after all those times on the sofa recovering from the night before unable to sleep with anxiety and feeling so very tired...torture...im back at work now but there is still the weekend;-)