It is hard to guess what will happen with soul when the body is gone. There is no straight answer in any religion, at least I have not heard of it. But few guesses could be done based on some cross-religious claims.
All claiming that there is something for the soul, but what is a mystery.
Lets make a mind experiment and imagine what it could be.
It is definitely a stress to leave the body and huge uncertainty on what to do. Soul most likely would act according to its instinct which reflect its "true believes". Whether looking for angels, seeking own prophet or the guide to destination place. And believes will lead to matching destination. Self-estimation or guilt are those instincts which fulfill the expectations and eventually define the fate.
There are few scenarios most popular among believers. Soul of Buddhist will seek for available fetus to become own reincarnation. Others will seek for holy spirit which will guide to paradise of own kind or fear the devil on the way to hell. Atheists will be lost in the choice and could become poltergeist or ghost as not able to choose own way. Perhaps there is a chance that some demon or gang of those will try to catch the lost.
As "smart" homo sapiens I would like to be prepared and select the path which will allow my soul to grow, gain experience and carry some mission in long run. The minimal step is to develop a curiosity with scientific approach on same level of strength as true faith. It is essential to keep the options open in order to preserve the progress. Sticking to same scenario is circling in rounds. The external factors will affect the path and rather following own agenda the stronger entities will be able to manipulate and use the soul. They also will try to keep them circling until reached wanted state or worn out.
Curiosity itself is not a path or agenda. The nearest and a step or two ahead plan would be handy. High-level agenda is declared earlier, how to achieve it?
Only known world is this one and potentially something in the middle. In this world we growing, getting enlightened or reverse. At least the progress here could be achieved for sure. So it would be logical to try to get back. One of declared ways is reincarnation. There are few others but less popular.
The self-improvement could be done on "carma" level. Which is unconscious and not reliable, most likely breakable by other stronger souls. Or on sane level. Which requires previous incarnations memory recall or at least same on soul stage. It has been claimed that most enlightened people could reach the level when previous lives recalled. Hmm, does not seem an easy option...
Are there other ways? Perhaps. There is a popular concept of conversation with dead people. Perhaps it would be the way to speak to yourself also? Seems it will require as gaining of whole xxx skills and ability of identifying yourself on top of it. Such approach would be quite dangerous to expose in modern society as not welcomed by any religion. On opposite the enlightening could be advertised and the help is much expected.
There is an effort associated in achievement of memory recall. As been read at least a decade to reach some approximation to "nirvana". Does it include the incarnations reunion in same consciousness or some more work need to be done? Adding the question to my todo list.
Despite of answers on questions above, the far goals of eternity should be leading to same conclusions as real life goals realized only inside of this world among live people. Be curious, learn and adopt knowledge, seek the path, state the goals and reach them.