How to back up shsh blobs and APTicket in iOS 9.1 in order to be able to downgrade to it after update? Just got a new iPAD air 2, iOS 9.1. It says I should update it to iOS 9.3.1. 
I might be interested to jailbreak it later on, so I'd like to preserve that option for me possible.

I hear jailbreak for 9.3.1 is not available yet, and on the other hand, apple stopped signing iOS 9.1 and it is impossible to install or downgrade to iOS 9.1. I want to know how I can back up the current state with iOS 9.1, and later after I updated the iOS, when ever I wanted I could restore to the iOS 9.1.

I know that I should backup shsh blobs using Tiny Umbrella. but I cannot find the official download file in their website.
Also I don't know how to backup APTicket.

Thanks
From your question, it seems you're mainly concerned with wanting to keep (or return to) iOS 9.1? If that's the case, then just don't update. 

If, however, you're concerned with your data, such as contacts, text messages, photos, etc then updating to iOS 9.3.1 is not going to result in you losing any of this data. 

If for some reason you've had to erase all data and start again with a newer version of iOS, then restoring data from a backup with an older iOS version works fine, so long as it is a backup from the same device.

So I guess what I'm saying is that as long as you have done a backup prior to updating iOS, then you will have no reason to ever go back to iOS 9.1. Even if you lost all your data, you'd be able to restore the data from your backup. 

Also, I want to add there are a lot of reasons why you should update to the latest iOS version as Apple has recently resolved a number of serious (albeit rare) issues that could have bricked your device.

Hope this helps. Any questions, just ask.