Your situation is commonly referred to as the '10 year itch'.
This means that having worked in a particular industry/function for a decade, familiarity sets in. And, as the adage goes - Familiarity Breeds Contempt - it is not uncommon for many 10 year itchers to crave change. And, the itch is particularly horrible to those who haven't risen as much as they would have liked to in that decade.
And, interestingly, the itch has a way of sifting people. While many fall off the perch, those remaining will use it to up-skill themselves and get fired up for the next decade - until the 2nd 10 year itch!
The first answer you really need to get right is WHY you want to shift from being an HRIS analyst? Is it that your work has become repetitive to the point that what earlier was a challenge is now routine? If this is true, then you are not alone. It happens to the best of us - that's why the itch is called the itch!
Second, why are you considering a HR manager's role? You say that due to your excessive interaction with them over the years you've picked up a whole lot of what they do etc... And, I totally agree with you. But remember, knowing about something and not being responsible and accountable for its delivery is a far cry from being responsible and accountable for it - day after day! And, that is why, almost all employers (at least those worth working for) will logically insist on prior HR functional experience from a managerial candidate.
Third, as fed up as you may be being a HRIS senior analyst, think 'outside of the box' and identify how those same skills can be best used in a different environment to achieve client results.
Here, I am referring to perhaps considering speaking with Management Consultants who specialise in HR. I am sure there will be some who can utilise your wealth of expertise (and I really believe that good analysts do possess a wealth of functional knowledge) to design products and service offerings which they on-sell to their clients for a fee. I know that if I was running even a relativel successful HR related consultancy, I would definitely want to speak with you.
Why? Because, with you I have 2 significant advantages.
First - Your knowledge is NOT biased with years of operational and implementation frustration. Thus, the inputs you provide in designing the product or service will be almost utopian (because while you know the theory, you haven't really implemented it). But, being a senior analyst, it will also be tempered with the requisite amount of risk advice. After all, a chief strength of any senior analyst is to identify process/function risks and suggest best options to mitigate those.
Second - You are a 2-in-1 package. You possess theoretical HR knowledge AND are invaluable in designing, developing, building, testing, and deploying the product.
Now, at first glance my suggestion may seem that I am asking you to do more of the same. But, read carefully!
Right now, you are part of the 'DOING TEAM'. What I am suggesting is to take that 'DOING' knowledge to the next level and become part of the 'STRATEGY and CREATE' team.
Believe me, you don't want to enter a ultra-competitive landscape (HR managers' job market) with only peripheral knowledge (seen from a employer's perspective) just because you're another involuntary statistic of the 10 year itch.
Instead, leverage your analyst's skills-sets coupled the wealth of process/system knowledge that you possess and give yourself a chance of experimenting with a slightly left-of-centre growth strategy. Never know which doors it may open into the future ...
I hope my response helped your internal dialogue and decision making process.
All the Best!