Antifouling - whether to strip down old paint instead of painting another layers?

[Sailogy]

I need to decide how to prepare the bottom of the hull of my GRP boat for the next seasons.
The boat’s history is following:
One and half year ago I have bought the Beneteau Oceanis 40, the construction year 2007. Upon buying, the hull was thoroughly checked for osmosis and it was OK. I’ve decided for the anti osmosis check because around 5 years earlier the boat had a major hull repair as a result of hitting an object. After buying the boat, their hull was painted with any International ablative antifouling paint. You can see the hull before painting in 2016 at the enclosed pictures (their names start with 2016 – first 4 ones)https://www.dropbox.com/sh/48you4r1w...J9CVj2Lka?dl=0.
During last 18 months, most of the time the boat was moored close to Athens at the Aegean Sea. The boat was hauled out recently and after pressure washing, I’ve found many patches have appeared as a result of peeling off the paint. The patches look similar to that from the previous year but they have appeared a little bit less frequently. You can see the recent pictures of the hull enclosed (their names start with 2017 – last 6 ones).
For the next few years, I plan to keep the boat as long as possible on water mostly on a permanent mooring with no more than 150 hours of sailing during the year.

What results should I expect after I choose any of the following options:
• Priming and painting with another layer of ablative paint?
• Remove all the layers and prepare the hull from scratch?
• Does it make any sense if I arrange painting for two seasons International Micron 350 antifouling paint without removing all old layers?
• Could Coppercoat be a solution for long-term cost effective solution for the yacht which will be most of the time on a mooring?

[Pete7]

What results should I expect after I choose any of the following options:

• Priming and painting with another layer of ablative paint?

There is a risk and almost certainty that the hull will continue to peel as you add further coats of antifoul paint.

• Remove all the layers and prepare the hull from scratch?

The best option all be it expensive.

• Does it make any sense if I arrange painting for two seasons

you can try but what about changing anodes etc.

International Micron 350 antifouling paint without removing all old layers?

It will peel becasue the underlying layers are not firmly attached to the hull.

• Could Coppercoat be a solution for long-term cost effective solution for the yacht which will be most of the time on a mooring?

See what other yachts with coppercoat are like before taking this major expense. Some folk have good results, others have had to paint over the top. I suspect those who sail continuously are okay, but marina queens foul up just as ordinary paint fouls up quicker if the boat isn't used.

Pete