Firstly sorry this post is so long, but thought I should set out all the details at the outset.
I work part-time over 4 days while the DCs are at school. I have 1 week-day off (sorry, I'm being deliberately vague with the details to avoid outing myself).
I work in a small department with an unpredictable and variable workload. The kind of work I do has to be completed to a schedule. If one date is missed, the whole schedule is scuppered. Sometimes there is too much work and outside contractors are used. Other times we have nothing to do. People generally work overtime when it's busy and take time off when it's quiet. I've worked in this department for 12 years, 8 of these part-time.
My boss has always complained that my being part time means they can't give me work as there aren't enough hours to do it by the required deadline. Sometimes my boss has had to outsource work, leaving me with nothing to do, which I hate - it costs the company more, and makes me feel I am going to be made redundant one day.
Now that both DCs are at school I've discovered I can be more flexible and do a few extra hours - staying a bit later, taking work home, even working on my day off if necessary. I have done all these on occasions.
So over the summer and autumn I racked up quite a few hours of overtime. I recorded the hours spent on the company's time recording system, which my boss is supposed to monitor and use in their reports to management.
Now that things are quieter I've tried to take an hour off here and there, with my boss's agreement, but they have been sniffy about it.
One day I left 30 minutes early (having finished all my work, and checked with my boss whether they had any more work - they didn't). I came back to a snotty email the next day - my boss apparently didn't know how many hours I had accrued (to put this in perspective, my boss arrives in the morning any time within a 30 minute timeframe. They have sometimes cancelled meetings without telling me, worked at home with no notice, come in 1 hour late without any explanation).
Obviously I only want to take time off in lieu when it's convenient to the organisation, ie when things are quiet, and give as much notice as possible.
But it has occurred to me now that my boss hasn't once said "thank you" for working the extra hours. I'm tempted to think "Sod it, I'll just work my fixed hours from now on", but might do myself out of a job ...
AIBU to expect thanks?