Losing blueprints when switching builds

[Blinky]

So I usually play using the experimental build but jumped back to 16.36 to play with some friends on their server. When I went back to experimental at a later date to continue with my current game I found that all my blueprints had disappeared.

a) is this intentional?

and

b) is there any way to get my blueprints back?

It's not really a big deal, I nicked most of the blueprints from various sources, but it's putting me off going back to my friend's server.

Thanks for your help in advance.

[Loewchen]

This is inevitable, your blueprints are stored in one file, this file works with the current version and can be updated, but if you use it in an older version the game will not understand it and overwrite it.
You might find some of your blueprints in your older save files.

[Blinky]

I was afraid that would be the case. Thank you, I’ll check the save files just incase.

[kreeg]

Check your %appdata%\Roaming\Factorio folder for a file named blueprint-storage-backup.dat change it to blueprint-storage.dat and you should be good to go.

[Blinky]

Check your %appdata%\Roaming\Factorio folder for a file named blueprint-storage-backup.dat change it to blueprint-storage.dat and you should be good to go.

Nice, I'll have a look later. Thanks for your help.