Many readers have written in with concerns over the latest Coolest Cooler updates, which were posted last week to the Coolest’s blog, and now presented in the YouTube video above.

In the video, Coolest creator Ryan Grepper explains the latest round of delays, which he says is due to difficulties with the motor.

Apparently, the initial motor manufacturing factory Coolest was using “has gone on strike.”

Unfortunately, the hunt for a new motor supplier has been an arduous road, according to Grepper in the video. He says they’re running vigorous tests to make sure the replacement company’s motor stands up to at least five years of blending icy drinks.

Grepper also makes the announcement toward the middle of the video, which blacks out here, to “sell some limited quantities of Coolest online this holiday season.”

He says “this decision was not made lightly,” but to “keep the lights on.”

Many users have already found the Coolest listed on Amazon at full price, $499. Yesterday, the Amazon post stated that “This item is currently unavailable because customers have told us there may be something wrong with our inventory of the item, the way we are shipping it, or the way it’s described here,” so sales were temporarily suspended.

Today, the Coolest appears back on sale.

In a Nov. 13 update, the Coolest posted about the motor strike/replacement search/testing cycle, Grepper wrote that the process was about four weeks out, putting production around the “week of December 20th.”

In the video, Grepper says production for Coolest to continue is now “four to six weeks” out.

“Given these variables, the best expectation that we have right now is that production will be starting up in January, and that the last of our backers’ Coolest will be rolling off the assembly line sometime in April.”

Grepper says they will continue posting updates on the blog.

Not surprisingly, Coolest backers are not happy with yet another announcement on the delay.

In addition to taking to social media, the as-of-now 96 comments on Amazon range from 69 percent at one star — who mostly appear to be backers who haven’t gotten their Coolest — to five-star reviews by 27 percent who presumably have received them. See a sample of Amazon’s reviews to the right.

In October, after one of the last updates, we talked with Coolest about an update on the process and were assured that everyone would eventually get their coolest by a company spokeswoman.

Grepper attributed the delay in the Oct. 15 post to some faulty manufacturing in pieces (no mention of a motor strike at that time), while they also told us a port fire and “larger than anticipated amount of people order[ing] accessories” was delaying the process.

As Coolest is one of the most backed projects on Kickstarter of all time — more than 62,000 people pledged a collective $13 million to fund it — there are a lot of unhappy Coolest backers out there.

We reached out to Coolest and are waiting for a company update.

Again, the company is offering full refunds for anyone — even those who purchased via Kickstarter — if they’d like to claim one.