Align the text of main, sub, and xlab to the left

Question

How can I left-align the text of main, sub, and xlab on openair?

timePlot(
    main = 'Liberty E -9',
    sub = 'Time Period: September 30, 2014 - June 30, 2015',
    allData,
    pollutant = c('PM2.5', 'humidity'), 
    avg.time = '1 hour',
    lwd = 2,
    lty = 1,
    name.pol = c('PM 2.5 particulate ug/m3', 'Device Humidity %'),
    type = "site",
    group = TRUE,
    auto.text = FALSE
)

I get all the text centered by default

But ideally, I want the text to be aligned to the left,

Is it possible? Any ideas?