you've already had 3 months, and you want another 6, that's not a holiday, you're trying to do border runs to cheat the system, why don't you get the correct visa instead of being a total prick and fucking it up for everyone else
It is precisely for people like yourself that they are changing the rules, you are trying to live in Thailand but without obtaining the correct documentation and paying for the priveledge
You should not have a problem entering again, immigration are looking for people trying to stay long term in Thailand without the correct visa, you are not extending your 60 day stamp you will be ok.
This is what happened to a guy who tried to extend another 30 days, the immigration gave him 7days to leave the country, its not a rule, dont rely on your immigration office doing this, there has been a misunderstanding that this has become a rule.