Yet another of our neighborhood whitetail deer.

I sowed my maincrop potatoes in one of the raised beds on 30th March, varieties were Mozart, Maris Piper and King Edward. All the seeds were chitted and planted using exactly the same method, however, the Maris Piper & Mozart have totally failed to grow, I mean not even broken the surface! The King Edward were my own saved seeds from last year and they are absolutely thriving, unfortunately, after digging a few of the others out, the chits are the same size as when they were planted. The MP & M were bought from the supermarket, but saying that, I bought MP from the same supermarket last year and they grew ok?

Some supermarket potatoes are treated with growth inhibitor, some not. Very hit & miss & won't save you money in the long run. Buying good quality seed potatoes is more reliable, safer regards viruses & keeps the seed merchants in business for next year.

Regards when to plant earlies and main crops- they don't go in early & late, they're faster or slower at growing & are ready early or late if planted at the same time!
Same goes for other early varieties such as peas. You can sow "early" peas late in the season & get a quick crop before winter because "early" just tells you how short a time it will be from sowing to harvest.

My Grandad always planted his spuds on Good Friday, whenever it fell.
I plant mine after the last lamb is born (also very variable) just because I have time then.
The weather plays such a huge part that they always seem ready about the same time whatever I do! 

Light clouds and a bit of sun but some rain forecast for later on.

Sorry to hear about your knees Aidy.
For years I suffered with arthritis and both my knees had been in steady decline, then in 2017 cartilage in the right one split - agony and I could barely walk. X-rays confirmed the joints were well past their best but at 57 the NHS said I was too young to be considered for joint replacement. Not what I wanted to hear but really glad they said that now as it set me off looking for an alternative.
Information was difficult to find at first but there seems to be lots more available now (go on YouTube and search "Knee joint cartilage self repair). A few simple exercises coupled with dietary supplements of glucosamine sulphate (available at big supermarkets), drinking chicken stock daily and eating Pollack every week soon had my knees back in better shape than they'd been in years.

Arthritis - fast forward to one year ago - Whilst looking at ways to avoid the looming spectre of type 2 diabetes I came across inflammatory foods. I knew about anti-inflams, been taking turmeric for years, but had no idea some foods actually cause inflammation, not just in joints but at cellular level so they contribute to all kinds of problems.
The big ones it seems are seed oils (vegetable oil) especially in solid form used to replace butter. Extra virgin olive oil's alright and ev coconut oil but those extracted using heat and solvents - canola, corn, palm, sunflower oil etc are best avoided.
To distance myself from type two I also cut out or reduced food with a high glycemic index - sugar, rice, taters and wheat flour. Amazingly, not only did my insulin resistance drop but arthritis quickly stopped being a thing. My joints are no longer painful or red and have full movement. No need to take turmeric either.

Not saying any of this is guaranteed to work but it certainly sorted me out. Maybe worth looking at.

Another 73 dispatched today Wife thinks I’m going slightly mad