Cisco ISR 900, IOS Upgrade?

[landingbuildingmanager]

Just picked up a Cisco ISR 900, and it came with IOS 15.8.3. I'm wondering am I able to upgrade to the most recent version 15.9.3? Is the licence permitted or will I run into issues?

Also, I had purchased the SEC-licence for it. I intend to load that - would the licence still be valid with 15.9.3?

Lastly, seeing that Cisco had discontinued Cisco Configuration Professional, and Express version, - is there an alternative method to configuring the router via web / GUI? I'm comfortable with CLI, but those that will be supporting prefer to look at a web-based tool or a gui. Is there any way for me to obtain such an interface.

Thanks,

[landingbuildingmanager]

Following up on this. I tried to download ios 15.9.3 recommended firmware version, and the website notified me that I need to have a support contract to obtain the upgrade. 

I'm confused a bit.

It seems that the end user purchases the hardware from the reseller. Then, they need to purchase a support contract for the hardware in order to obtain an update to the already loaded ios? Further, if they require any additional features, then, they also need to purchase a licence for those features. Is that correct? Or am I missing something. I've done 2 of the 3 items so far, in purchase the hardware and licence for features, but now, I'm missing the support licence to obtain an upgrade to the software.

Then whatever happened to the CCP and Express versions - that because they're retired (End of Life). The end-user cannot obtain a GUI / Web Gui interface to configure the router.