A big increase in migrants at the US-Mexico border is expected

A pandemic public health order has been in place that stopped many migrants

(CNN) - More migrants are coming to the US-Mexico border, and officials say they expect the number to grow.

This is something we've seen many times before.

Some key details are different this time around.

Here's a look at what's changing, why it's happening now and why it matters.

For two years, a pandemic public health order has been in place that stopped many migrants from crossing the border and seeking asylum in the United States.

The policy is known as Title 42 for the US code invoked in its implementation, and its days may be numbered.

Under that policy, authorities turned away migrants more than 1.7 million times, expelling them into Mexico or back to their home countries, according to Customs and Border Protection statistics.

Now there's a big bottleneck of people waiting to cross.

The rule that stood in their way is likely to be lifted.

Three US officials told CNN the Biden Administration is planning to end that public health policy on May 23.

An announcement could come this week.

Officials appear to be giving themselves a cushion to plan for the possibility that the number of migrants at the border will significantly increase.

For days now, they've been telling us it will.