It appears that some people are trying to by-pass the roadblocks, by using the Trans Australian Railway access road

Snip from ABC News

Acting Police Superintendent Craig Davis said motorists have attempted to bypass the road closures by driving on unsealed bush tracks which he said is reckless and dangerous.

He said there have been a couple of incidents over the past week where police have had to rescue motorists who became bogged in a remote area near the Trans Australian Railway.

"Our advice is please, do not try to take alternative routes," he said.

"It is chewing up our resources when they get bogged or stranded and then we have to take action to get them free."

Also some motorist at Caiguna, are getting a bit hot under the collar

Here is what the Manager of the roadhouse has to say

Ms O'Halloran said the truck drivers are used to life on the road and have been patient during the delays, but some holidaymakers have lost their cool in the scorching summer heat.
"There's been a few tempers here and there but we're coping," she said.
"We're trying our best to service people. The hardest thing to service is people's aggro.

Link below

https://www.abc.net.au/news/2020-01-01/road-closures-cause-nullarbor-travel-chaos/11836476?WT.ac=statenews_wa