We're expecting a big increase in migrants at the US-Mexico border. But this time is different

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. But 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.

There's a huge backlog of migrants waiting to cross

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 are 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.