You could approach supported housing providers, by that I mean services focused upon individuals rather than general needs housing that tends to focus on bricks and mortar.
For oneexample of many, homeless hostels that deliver 24/7 services are always in need of relief staff as they need to be staffed 24 hours every day of the year. If you work it out, for every 5 -6 full time staff they employ they will need 1 full time equivalent for cover purposes (holidays, training, illness, etc)
The odd shift covered whilst remaining in your current employment typically leads to more and more shifts and you then gain experience of these person-centred services and can then apply for similar positions when they become available. The skills learned are also transferable ones to much of general needs housing.