There are some standard problems in X-Wing that can be seen again and again. Turning a swarm while maintaining a broad front is one. I’ve seen this one on a recorded game and it got me wondering how to continue without making range control easy for an opponent.
Moving in close formation is often unnecessary. But it’s also super cool! Maybe you shouldn’t return to a close formation. Here we assume that you want to – whether that decision is correct or not.
The problem

You wanted to turn your ships into the board, but slowly with banks. For whatever reason, you did not use the bank+1 method. Maybe you forgot and it was simply a mistake. Maybe it would have been right, but the situation changed. Whatever the reason, now you have your ships behind each other and want to reform a close formation.

The solution with boost
There are two close formations you can easily move into: a line or a V shape.

To get into a line formation, your ships have to 1 bank for Red, 1 straight and then 1 bank for Green, and 3 straight and then 1 bank for Yellow. That forms a close line.
If you want to form a V instead, you simply have to change Yellow into a 3 bank as shown below.

The solution with rolling
Maybe your ships have a barrel roll instead of a boost and you want to use that. I didn’t find a way to reform a line. But you can form a very tight triangle formation. Red does the 1bank and rolls to the right. Green and Yellow both do the 3bank to catch up.

The solution without boost or rolling
You can’t. You need an intermediary step. For example, you could move with increasing straights, followed by a turn of the bank+1 method. But in that case, you can also simply choose the maneuvers from the solution with boost instead.