I have been given no choice but to accept the job being given to me

I am due to return back to work at the end of July. I was working full time prior to my maternity leave and felt that discussions about me returning part time were constructive and supportive. However it wasn’t until I came away that I realised I have been told what I will be doing and have had no say in this final decision. They are only allowing me to return on 18.5 hours a week which is 3.5 less than was originally discussed and significantly reduces my pay. It is only due to some significant life changes since having my son that these reduced hours are financially possible. I feel that I have been given no choice but to accept the job being given to me and made to feel that I should be grateful for it even though financially this could have lead to me having to leave my job.
Scares me how they go about it to make you feel it was a decision that involved you when in actual fact you’ve come out with nothing you originally wanted.

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