I am going to visit Gulangyu Island in Xiamen in April this year and get the lowest air ticket.

Generally, the price is lower in April, but it can be lower in early April, because the end of April is closer to May Day, so the fare will rise. I suggest you go around April 10. And the departure date. Try to avoid Friday and Saturday. Generally speaking, the weekend is the peak of travel, and the fare will go up. As for booking tickets, the earlier the better, of course, but one month in advance is usually the lowest price.

If you live in Gulangyu Island, Fish House Hotel, Slow House and Carambola Garden Coffee Hotel are all suitable for couples to stay in, and the surrounding environment and the internal atmosphere of the hotel are not bad. I booked it on Ctrip. I think it's ok.