Lindsay Lohan -- Down to the Wire ... Community Service COMPLETED!

Lindsay Lohan will get a letter of completion from her London community service center ... but it will still be warm off the photocopy machine when her lawyer hands it to the judge.

Sources familiar with the situation tell TMZ ... Community Service Volunteers will certify Lindsay has completed her 240 hours to satisfy her probation requirement in her reckless driving case.

As we reported ... Lindsay waited until the last minute to get it done, and she put in her time at a breakneck pace beginning late last week.

There's one thing that's unclear ... whether she completed her hours on Tuesday or whether she has a few left that she'll do Wednesday before the court hearing. Since London is 8 hours ahead of L.A. she has the full day to finish if she hasn't already.

We're told CSV is prepared to send a letter of completion before her court hearing Wednesday morning.

Lindsay was supposed to complete her hours November 6, but she had only performed 102 hours of the 240.

Lindsay will not be in court. Her lawyer, Shawn Holley, will hand the sacred doc to the judge.