Job posting with starting date far away

This is not a red flag, a lot of companies plan ahead, be it from financial or people side.

But there is an important note to make, 6 months is not a short period of time and a lot of things can happen from now until then. You can be hired and then, after 6 months, find out that the position is no longer available due to reason X, Y, Z. Be prepared for this and prioritize positions with the start dates either immediately or weeks/several months max.

I have see this in a few situations that are 100% normal:

• college internships work this way.
• some teaching jobs work this way.

Some other situations can occur when the position is linked to the company winning a contract. The offer will be contingent on them winning the contract. If they don't win the job disappears. One of my kids applied for a job with such a contingency. They interviewed in August, and would find out if they won in November; if they did win the job started in January.

It can also be linked to a position being funded after a certain date. I have been a part of contracts where a position wasn't funded until year 2 of the contract. There was no need for most of the help desk positions if the product hadn't started production.

Knowing before you apply is better than knowing after you have completed multiple interviews.

I admit, I've not seen a posting that'll open up in 6 month, but that does not necessarily mean it's a red flag. There might be several reasons for a timeline like this, including spinning off a new department / business unit etc.

I'd say, if your profile is a fit, go ahead and apply. You'll have plenty of time to evaluate the offer also.