25B Reclass?

I can't tell you what it's like being a 25B or even how to reclass to be one in the Reserves. They are a different beast.

What I can tell you is that with your employment history and certifications you may be able to contact the 25B MOS proponent at the school house and be accessed under the ACASP program, Army Civilian Acquired Skills Program, into a new MOS, probably without training, or with shortened training. Of course you'll have to find a unit with that MOS

I’m currently an Active Duty 25B. I’ll say that any decent 25B has security+ as it is typically a requirement to attain admin credentials on most military networks. If you are truly passionate about IT I would recommend you to reclassify as a 25D or 17C if that is an option for you. 80% of 25B’s end up doing basic helpdesk technician duties while 25D’s and 17C’s do more networking engineering, cyber defense, cyber exploits (AKA the cool stuff). Not to knock you at all 25B’s have it good 17C’s and 25D’s just have it better.

Most 25B's have to acquire those certs on their own time/dime depending on their duty assignment, so you definitely have a leg up. I can't speak much to the reserve side of the house but 25 series are always in high demand on the Guard side. Reclass is a couple months and multiple phases for reserve component. Again not sure if that's unique to Guard or Reserve as well. The ATRRS Course info for the school you attend will have guidance on how to prepare for the course. Best of Luck!