There is no "day to day" duties of IntOs in NAVRES.
There are no "Intelligence Officer" positions in the Naval Reserve.
First, let be clear on what I mean when I say, “the Naval Reserve”. I don’t mean everyone who is a naval “reservist”, I mean the specific collection of units and organizations that make up the Naval Reserve. This includes the 24 Naval Reserve Divisions (NRDs), the Headquarters, and to a lesser extent, Naval Fleet School Quebec (which technically a part of a Reg Force organization (NPTG), but for all intents and purposes, it’s a Reserve unit).
Second, let me be clear on what I mean by “Intelligence Officer Position”. There are a few positions within the naval reserve that specifically call for an Intelligence Officer, such as the Intelligence Section’s divisional officer position at NRDs, the IntO training officer(s) at Fleet School, etc. However, there are no positions (yet) within the Naval Reserve where Naval Reserve Intelligence Officers will be asked to perform actual intelligence gathering and analysis, and production of intelligence products.
So, if you are an IntO working within the Naval Reserve (full time or part time), all you will be doing is administration, and lots of it, most having nothing to do with Intelligence. You’ll be a divisional officer responsible for junior officers or junior sailors (IntOps), and you’ll take on whatever projects your department head wants to send your way. You could be overseeing the construction/implementation of a new security network at your building, performing a research project on the acquisition of radars for the unit, developing a training plan for the Intelligence section, assisting the OpsO in designing whole unit/regional training exercises, etc…
Every now and then (6 weekends throughout the year) there will be Naval Reserve “Intelligence Officer Training Weekends” across the country that you can sign up for. I have no idea what happens at these weekends, but I hear there’s lots of beer and shenanigans. I believe the most “advanced” intelligence products that they produce over these “training” weekends is summaries on different nations, military equipment, and world leaders, all using open source intelligence. Whether these products actually get distributed for use, I have no idea (maybe someone can confirm?).
Now, that all being said, there ARE opportunities for a Naval Reserve IntO to work as an actual Intelligence Officer, but all of these jobs are outside of the Naval Reserve. You can go on overseas deployment in Bahrain or Iraq, you can sign up for exercises like RIMPAC, or you can take a long term contract working at TRINITY, which is the Maritime Operational Support & Intelligence Center (MOSIC) in Halifax. You’d be doing actual Intelligence Officer work, but TRINITY is a Regular Force unit, so not “within the Naval Reserve”.
Hope this helps.