Help-how much will Ramadan/Aid il Fitri impact our travels in Indonesia?
 

We just found out (thankyou, marmot!) that our September trip to Singapore and Indonesia falls within Ramadan and Id al Fitr. I wouldn't expect this to be much of an issue in Singapore. But how much will this interfere with travel to /within Java and Borneo and islands? Should we consider changing our travel dates or destinations?
Would Bali be a good alternative? Suggestions appreciated.

why would you change...? it should have little affect on your travels..

I wouldn't change plans. They're a little more relaxed about this in Indonesia. Unlike much of the Mid-east, restaurants don't close during the day (a few of them do but most don't) so you won't have much problem finding a place for lunch. Dinner might be a bit more of a problem, since many places get packed.

People do end up traveling a lot around Eid, so that may be your biggest issue if you're trying to get somewhere at the same time. You couldn't pay me enough to take an Indonesian ferry around Eid, and airports will be quite jammed.

As others have posted, many people travel by land and air to go to their home villages during the period leading up to and after Idul Fitri. If you travel by air, it shouldn't impact you at all. However, the long-distance roads, train stations and ferries will be jammed, so you want to avoid that at all costs. I go to Java quite often during the fasting month, and it doesn't impact me at all, except that friend who sit with me in cafe's politely decline to eat or drink. Alcoholic beverages will be harder to order in restaurants. Bali during September will mostly be as usual, you probably won't notice the holidays at all, except there will be less Javanese and Sumatran businesses and workers around.

Two different issues: The fasting month, Ramadhan, and the holidays that follow, Idul Fitri or Lebaran in Indonesian.

Ramadhan isn't my favorite time to travel in Islamic Indonesia because people are tired and grouchy. If you take long distance car or bus trips you have to be careful not to get a sleepy driver.

In Jakarta and most of Java local restaurants are closed during the day. Hotel and "international" restaurants remain open. Cultural activities and performances are curtailed.

Bali isn't affected by Ramadhan. Areas of Indonesia that are split culturally like Kalimantan (Borneo) and Sulawesi are less affected.

During the holidays following Ramadhan millions (literally) of people are on the go, mostly surface -- trains, cars, buses, ferries -- but also flights. You have to secure reservations in advance. This is also a popular time for travel to Bali, for Indonesian and for people from other countries that celebrate the Islamic holidays so, again, you have to reserve in advance.

My personal advice would be to reconsider visiting Java during Ramadhan or at Idul Fitri. I believe Borneo would be okay but you should ask the resort. Sulawesi would be a good alternative for diving.