I currently receive assistance from Obamacare, but recently got a job that provides healthcare to its full time employees. Do I wait until the next open enrollment date to change my insurance, or do I change as soon as possible?
If you get a job that offers health insurance you'll want to drop your ObamaCare cost assistance and most likely want to switch to the employer plan. This is because people with access to affordable employer based health insurance don't qualify for cost assistance like tax credits. If you take tax credits after the point employer based coverage would have started you can end up owing back tax credits at the end of the year for the months you improperly took them. Make sure to let the Marketplace know when the new coverage starts so you can cancel your old plan on or very close to the date the new coverage starts. As long as you have less than a full month without coverage in between insurances you won't owe the fee for that month. Lastly if you gain and then lose employer based coverage (for any reason other than fraud or non-payment) you will qualify for a special enrollment period to switch back to Marketplace coverage.
Please note that if you get a job that doesn't offer you health insurance or want to stay on a private plan that doesn't offer health insurance (even if it was purchased on the Marketplace you can.) Just keep in mind your employer only offers one chance each year for you to enroll in their coverage, so if you decline coverage you can miss your opportunity.
Also keep in mind, that only those offered coverage through the employer are barred from getting cost assistance. If coverage isn't offer to a spouse they can retain Marketplace coverage.