<human>: Can you provide a brief overview of the text?

My then-boyfriend proposed last June. Of course, I said yes. We were planning to get married June of next year. June 14, to be exact, and I've already begun placing deposits on the venue and church to block off the date.

His sister is married to a foreigner and they're currently based in Europe. In the first place, we chose that June date because school lets out, so it shouldn't be a problem for both his nieces to come with. I should mention he is her only sister and they are extremely close.

Here's the problem. I get a call from his sister saying June's a bad idea because there was some issues with their papers/Visa/job and they might be moving to a new country/continent altogether around that time next year. She asked me (very nicely) if I could move the wedding to October because she really wanted to be a part of her brother's special day.

I don't know what to do. Part of me feels it's a long ways off to move it again. Specially after I've made deposits already. Another part feels i should do it to make everyone happy, including my future in laws and my future husband.
What should i do?
<bot>: Chose wedding date so that fiance's sister can make it. Immigration/legal issues come up so she wants wedding moved by 5 months.