The Foreign Service Institute puts Thai in its harder band: on the order of 1100 classroom hours for a full-time student to reach professional working proficiency, with at least as much again in private study alongside it.
You have done roughly 360 hours, self-directed, while living in the country. It is worth saying plainly that this is not professional proficiency and that no method reaches it in six months.
What it plausibly is
Somewhere around the FSI's level 2: able to handle routine social and work demands with a speaker who is willing to accommodate you. About 2000 words. The grammar essentially complete, which in Thai means something it does not mean in French, because there is very little morphology left to acquire. Reading at a slow but functional speed.
The living-here part is not a rounding error. 360 hours of study in Thailand is worth considerably more than 360 hours of study in Lyon, because every one of them was tested the same day.
- พูดภาษาไทยได้pʰûːt pʰaː.sǎː tʰaj dâːj
can speak Thai
true
- ยังไม่คล่องjaŋ mâj kʰlɔ̂ŋ
not fluent yet
also true, and the more useful of the two
What you will still not have
Native-speed listening between two Thai people who are not addressing you, which is a different skill from conversation and arrives much later.
Idiom. Regional speech outside Central Thai. Any register above the everyday: the newspaper's ซึ่ง and its formal vocabulary is close to a second lexicon. And humour, which is the last thing to arrive in any language and the clearest measure of how far there is left to go.
The maintenance question
From here the deck matters less than the exposure. Keep the sentence cards for what living here does not give you on its own: low-frequency vocabulary, reading speed, and the specific items you found fossilised in week 25.
Let the rest go. Greetings, numbers and the first five hundred words are now maintained better by Thursday at the market than by any review schedule, and continuing to review them is a way of feeling productive while not improving.