In order to root the new update firmware you need the SPFT release and the scatter file that is included. With that you can flash the TWRP via SPFT. I wouldn´t recommend using scatter files from older ROM releases, the partition offsets might be wrong and you risk bricking your phone.
The SPFT version of the current OTA update should be available soon.
Also you shouldn´t have to downgrade to MM in order to get the update. OTA packages are usually not released simultaneously to all devices. It might take some time before you receive theupdate notification. Also rooted phones might not receive the update notification at all, because their system has been modified.
Medard22 replied at 2017-7-15 23:14
In order to root the new update firmware you need the SPFT release and the scatter file that is incl ...
Thanks you for the answer, so when i was running 6.0 my phone was good but very hot in charge, and fingerprint sensor was not very quick, these 2 problems are solved in the new OTA, battery problems too ans i did not run into any bugs
The SPFT package is online. Adnan was right eventually. The first 7.1.1 ROM released in June was changed to a public beta according to description in the latest ROM. That means that current N users will not receive the OTA. You have to either downgrade to MM and then flash the OTA, or flash latest ROM via SPFT directly.