Johnny, I suffer horrendous migraines and have had 1 at w3 and then at w5 of Tx both lasting 4 days and I tried everything I could - painkillers either no relief or just a few hours; tried essential oils; voltaren gel etc, couldn't shift it, resolved on its own.
I looked at that link you posted I hadn't seen a recipe like that before - it seems a high concentration of salt.
I do use Sea Salt and/or Himalayan Rock Salt - because it is unrefined and contains other mineral salts, including Magnesium - which is often recommended for Migraines; the lemon Juice for Vitamin C - many people claim this helps reduce incidence of attacks but this is anecdotal, there's not much research available to explain why.
I did find a lengthy research article on migraines and its triggers and it mentioned 'high intake of salt' as one! But Magnesium, Vitamin B and some other nutrients (shown to be lower in people with migraines) given in higher doses did help reduce attacks.
I'm on Sof/Dac and have been sweating a lot and feeling dehydrated and drinking heaps of water = lots of 'peeing', which flushes out water soluble supplements.
I have started using the Himalayan salt to make an electrolyte drink - I put 2-3 crystals and a big squirt of lime juice into my filtered water bottle, shake it up, and sip away- especially next to my bed at night.
I'm waiting to see if it helps.
I'd be interested in how you go if you try that recipe, it's not the amount of lemon juice - that depends on the size of the lemon
2 tsp's of salt seems a lot.
Good Luck and if you find anything that works let us know