Elections BC has received referendum ballots from nearly two-in-10 registered voters, data released Friday shows.

After reporting a measly 6.5 per cent had been received as of Wednesday, the new number is a big jump. Elections officials said previous counts included only ballots that had passed initial screening.

The latest number – about 597,300 – includes all packages that have made it to Elections BC's offices.

And it's possible more are waiting in mail sorting facilities. The latest total does not include packages received by Canada Post but not yet transferred to elections officials.

Earlier this year, the agency's chief electoral officer said the Canada Post labour dispute was being closely monitored by Elections BC for any potential impact during the mail-in referendum period.

Ballots need to be at the Elections BC office, not just in a mailbox, by 4:30 p.m. on Nov. 30.

Voters are being asked to choose whether the province should adopt a proportional representation model, or stick with first-past-the-post. Not sure what the options are? Here's a quick explainer.

The slow trickle of submissions may not be unusual, as data posted by Elections BC on the HST referendum in 2011 showed a similarly slow stream of ballots for the first weeks of the campaign.

Many were mailed about a month in, and with a total of 1,653,528 votes by the end of the two-month period. The estimated turnout of that referendum was 49 per cent.

The last time B.C. voters were asked to reconsider the way governments are formed was during the provincial election of 2009, when turnout was estimated to be about 51 per cent.

The number of ballots sent in so far this year suggests some may still be making up their minds. Some experts say the decision could be as simple as which political party a voter supports