Welcome to the Q&A Forum

Hey guys, I'm in the process of re designing my company website. This website runs in Kentico CMS and now I'm moving to drupal CMS. The main reason for the move is that I need a more flexible design with responsiveness and integrate better social aspects. Currently I'm having to deal with a developer whom can't be bothered to update the site. I also find kentico extremely difficult to deal with. The site has good Google rankings and I was thinking about setting up some 301 redirects when the move is completed. Now the question is this site is been live for over 2 years and I have tons of blog posts sitting in here. How can I get these moved? When this is done will they lose their 'age' ? What if I re create the blog posts as it is and then setup 301 re-directs on this? I have G+ authorship and will they be affected by this? Last question is having a responsive site will affect my SEO rankings once moved? I heard the 301 is not considered as a 'safe' thing with Google so what are my options? If anyone can share a link(s) to site upgrades/moving to new design tutorials/best practices articles based on SEO ill be grateful. Thank you very much.