Not sure your plan will work as you describe. not an expert- but I see 2 issues:
1) If you are 50 now, you can get tax relief on max 30% of your salary going into a pension, so only 9k per annum.
2) If you have a public sector job, and you can avail of whatever work pension scheme is on offer for that employment, you can’t contribute to a separate pension scheme unless you have additional earned (employment) income not covered by your main scheme.
you can make AVC to whatever scheme is offered through work, using the max above minus any contributions required to the main scheme