A friendly reminder: While the political world remains enthralled with the upheaval inside the House Republican Conference, a series of legislative deadlines are moving ever closer — and the lack of an obvious successor to outgoing Speaker John A. Boehner hasn’t changed that.

The Congressional Budget Office delivered the latest reminder Wednesday, updating previous guidance on the most serious of those deadlines — the approach of the federal debt ceiling.

Should Congress fail to act to raise the debt limit, according to the CBO, “the Treasury will begin running a very low cash balance in early November, and the extraordinary measures will be exhausted and the cash balance entirely depleted sometime during the first half of November. At such time, the government would be unable to fully pay its obligations, a development that would lead to delays of payments for government activities, a default on the government’s debt obligations, or both.”

That assessment moves forward the CBO’s previous deadline estimate by several weeks and largely comports with the Treasury Department’s latest guidance, which predicted the ceiling would be reached on or about Nov. 5.

So what is Congress going to do about it?

With questions swirling about who will succeed him — and whether he will even be in a position to leave on his preferred date of Oct. 30 — a Boehner aide on Wednesday said lifting the debt ceiling has not been taken off the table.

“The Speaker has made it clear that he wants to solve some outstanding issues before he leaves. No decisions have been made, but a resolution on the debt ceiling is certainly possible,” the aide said.

Boehner has said there is unfinished business he intends to tackle before leaving office: “I don’t want to leave my successor a dirty barn,” he said shortly after announcing his departure.

But he has not specifically mentioned the debt limit, and there is plenty of reason to think that pursuing an extension would be too politically treacherous, even for a lame duck speaker.

Most Republicans will be unwilling to support any debt limit deal that does not include offsetting spending cuts, and President Obama says he doesn’t intend to negotiate over the debt ceiling. Boehner, who was unwilling to shut down the federal government ahead of an Oct. 1 budget deadline, is thought to be even more unwilling to risk a national default.