Just wanted to know that while exporting from the New UX is there any way in which the pdf export format be obtained as an A3 page. Currently the export is landscape oriented by default so is there any way out that this can be changed.
Yep. You can configure the page settings based on your printer type. So, click on the printer, change the printer that has the A4 ability, change to portrait, and you're all set. Alternatively, you can use the PowerPoint Add-In. Bring the chart(s) to PowerPoint then print from there any size you want.