When my Brother in law died abroad leaving a 16 and a 17 year old n a flat without parents ( my sister died when then they were 5 and 6) I went over for 5 weeks to stay for the beginning of the school term as my DN was in a terrible way and just staring his first A level equivalent year. Luckily that started 10 days after DS' s atart of his first year of school ( he was 5), so I was able to be there for ds's first wek of school but I had a lot of guilt about not being there for his whole first term
I left him home with DH but wanted to keep a daily connection with DS. It was more difficult to make video calls in those days but before I went I made a calendar with all the days I was going to be away .
On some of the days ( 5 in each week) I put a picture of a woman at a computer to represent a video call from me . Then on random other days there was a picture of a book or a wrapped present. I bought about 9-10 new books and 4-5 small presents wrapped up with DH . Every time they was a book picture , ds got a new book and I would sometimes get him to show me the book next time I called.to.twll.me.about it . We also talked obviously but the book gave us something tangible to share . 1-2 a week there was also a small present with a note from me that DH read out
DH said it was really helpful when DS would ask when I was coming home . He would cross each day off the calendar with him and also they would look forward in the short term to the next book or present or call. That way it didn't seem such a long time all at once.
Anyway we got through it so I would go if I was you but maybe for 3-4 weeks rather than 6 weeks
We also talked to the school so they knew why I was away and also.tried to explain in simple and non scary terms why I would be away for a while
As for the arrangements, absolutely do not send your child somewhere that is going to make her cry because she is avared of a bully. Get you husband to take leave, even if it is unpaid to cover those days. Or make some other arrangement. We also had nonbody to help, DH rearranged his work and ask for a temporary flexible working option. It was only for a few weeks .